Hydrophilic colloid composition

Abstract

A hydrophilic colloid composition having hydrophobic material dispersed therein and comprising an anionic surface active agent further comprises a cationic surface active agent in an amount sufficient to reduce the viscosity of the composition, the cationic surface active agent comprising a hydrophobic moiety, a non-ionic hydrophilic moiety and a cationic hydrophilic moiety.

What is claimed is:  
     
       1. A hydrophilic colloid composition having hydrophobic material dispersed therein and comprising an anionic surface active agent in the hydrophilic dispersion characterised in that the composition further comprises in that dispersion a cationic surface active agent in an amount sufficient to reduce the viscosity of the composition, the cationic surface active agent comprising a hydrophobic moiety, a non-ionic hydrophilic moiety and a cationic hydrophilic moiety. 
     
     
       2. A composition according to  claim 1  wherein the cationic surface active agent has the structure                    
       wherein 
       R 1  is an alkyl, alkenyl, alkylaryl or arylalkyl chain having from 8 to 20 carbon atoms or a partially or fully fluorinated alkyl, alkenyl, alkylaryl or arylalkyl chain of equivalent hydrophobic strength e.g. having from 4-14 carbon atoms;  
       R 2  is hydrogen, alkyl having from 1 to 8 carbon atoms e.g. methyl and n-butyl, or benzyl;  
       R 3  is hydrogen or alkyl having from 1 to 4 carbon atoms e.g. methyl (preferably R 3  is hydrogen if the sum of n and m is greater than 0;  
       X −  is halide (preferably Br −  or Cl − );  
       L represents a suitable linking chemistry between R 1  and the positively charged nitrogen e.g. a covalent chemical bond or —(CH 2 CH 2 O) x —;  
       each m and n independently is 0 or an integer such that m+n is 2 to 30, preferably 5 to 30, more preferably 12 to 18 and most preferably 15; and,  
       x is an integer from 2 to 30, preferably 5 to 30, more preferably 12 to 18 and most preferably 15.  
     
     
       3. A composition according to  claim 2  wherein 
       R 1  is an alkyl or alkylaryl group having from 10 to 20 carbon atoms;  
       R 2  is alkyl having from 1 to 4 carbon atoms e.g. methyl and n-butyl;  
       R 3  is hydrogen;  
       L represents a covalent chemical bond; and,  
       m+n is 5 to 30, preferably 15.  
     
     
       4. A composition according to  claim 2  wherein 
       R 1  is an alkyl or alkylaryl group having from 10 to 20 carbon atoms;  
       R 2  is alkyl having from 1 to 8, preferably 1 to 4 carbon atoms e.g. methyl and n-butyl;  
       R 3  is alkyl having from 1 to 4 carbon atoms e.g. methyl;  
       each m and n independently is 0;  
       L represents —(CH 2 CH 2 O) x —;  
       x is an integer from 5 to 30, preferably 15.  
     
     
       5. A composition according to  claim 1  or  2  wherein the cationic surface active agent is present in the composition in an amount from 0.1 to 0.5 equivalents relative to the amount of anionic surfactant in the system. 
     
     
       6. A composition according to  claim 1  or  2  wherein the hydrophilic colloid is gelatin. 
     
     
       7. A composition according to  claim 1  or  2  wherein the anionic surface active agent is selected from sulphosuccinates, alkyl ether phosphates, alkyl sulphates, alkyl ether sulphates, alkyl sulphonates, alkyl ether sulphonates, aryl sulphonates and aryl ether sulphonates. 
     
     
       8. A composition according to  claim 1  or  2  wherein the anionic surface active agent is present in the composition in an amount from 0.5 to 2.0 percent by weight based on the weight of the total system. 
     
     
       9. A composition according to  claim 1  or  2  wherein the hydrophobic material is a photographic coupler. 
     
     
       10. A photographic material comprising a plurality of hydrophilic colloid layers including at least one light sensitive silver halide emulsion layer wherein at least one of the hydrophilic colloid layers is formed from a composition according to any one of the preceding claims.